#pragma once
#include<stdio.h>
#include<stdlib.h>
typedef int mydt;
typedef struct NodeList
{
	struct NodeList* fro;
	struct NodeList* def;
	mydt val;
}NL;
void NLinit(NL* head);
void NLtailadd(NL* head, mydt x);
void NLprint(NL* head);
